<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
</head>
<body>
<div id="app">
    v-text:<span v-text="num"></span>
    v-text:<span v-html="num"></span>

</div>
<script type="text/javascript">
    var app = new Vue({
        el:"#app",
        data:{
            num:"<h2>Hello</h2>"
        }
    })
</script>

</body>
</html>